Improvement in bit-braces



tttiirt Sitic taai esta.

Letters Patent No. 110,960, dated January 17, 1871 antedated January 14, 1871.

IMPROVEMENT IN BIT-BRAcEs.

- The Schedule referred to in these Letters Patent and makingpaxt of the same.

To all whom'it 'may concern? Y Be it known that I, WILLAM. PENDLETON DoLIN, of Charlottesville, in the county of lAlbemarle and State of Virginia, have invented a new and useful improved Brace; and I do hereby declare the following to be a full and correct description of the same, reference being had to the accompanying'(lrawing, in whichv Figure 1 is a side view of my improved brace; y

Figure 2 is a longitudinal central section of .the saine;

Figure 3 is a side view of one of the ratchctewlreels; and y Y Figure 4 an end viewot the bit-holder.

The same part, is marked by the same letter of reference in the severai gnres where it occurs.

The nature of the invention consists in giving to Athe brace such construction and adjustments that it will receive and hold bits of'any-sizedshank, and that it may be operated, either in the ordinary manner or as a ratchet-tool, for boring holes in positions imac.` cessible tothe ordinary brace, all as hereinafter more particularly setforth. v

The construction of my improved brace is clearly illustrated by the drawing, wheren A marks the Vhead of the brace, whielris pivoted to and turns on the slotted arn1':iB. This arm has the slot tin it, through which the set-screw a passes into the arm to tix the two arms together in the desired positions. The position shown in iigs. l andi! is that which the head holds when the brace is used as a ratchet- Itool; but when theV brace is to be used in the ordinary manner the set-screw c is loosened, and the arm B is turned upon the arm C until the center of the head A coincides with thecenter ot' the spindle c at the upper end the crank DV of the brace, (see lig. 2.)

-Thev arm C is enlarged at one end, as, shown, for the reception of the spindle c, which serves as the Vupper journal ot' the crank D5.

The end of the spindle c is threaded, and receives the unt b, which passes into a counter-sink in -the enlarged head of arm C.

f The lower end of the crank D carries the devices for holding and operating the bits.

-Two ratchet-wheels,'E` F, with u, teeth set in opposite directions, are fixed4 on a spindle, c, by means of a'feather (see lig. 3) in the bore of the wheels,` enter-4 threaded shaftcr, 011 vwhich the interiorly-threadcd sleeve' H screws up and down.

A'To' shaft G are'pivoted, at t @the jaws I K, which form the bit-holder. They are held `apart by the springs s s, counteracted by the movements of the sleeve II, which, as it isserewed down, brings the i jaws nearer together, and, as it is screwed in the op-V posite direction,.allows,the jaws 'to` move apart in obedience to the springs s s.

Each jaw has a rectangularnotch in it, and when the jaws 'are in contact these notches form -a square Y hole, as shown in iig. 4.

It is obvious that the jaws, thus constructed, can Y be made to receive and hold a bit with a shank size within the limits ot' their movements.

The operation is as follows: The bit to be used is insertedv between the jaws I K, and the sleeve screwed down till the bit is held firmly in place.

It' the brace Iis to be usedin the manner-of 'allor-Tf? diuary brace, both pawls arefthrown intogcar, and.

the center of the head A is placed over the upper 1 end of spindle c and there fixed bythe set-screwc.

If the brace is .to be used-for boring a hole in the corner of a. room or against a wall, or in other position inaccessible to the common brace, the head-r A is' turned around to the position shown in figs. 1 and 2, j;

and fixed in that posit-ion by the set-'screw a. The; proper pawl to impart the boring mctio'nto the bit is'.

then thrown into gear, the otherone being disengaged,

The operator, now pressing uponfthehead A, works the crank I) back and forth, and; the boring is eiected by the operation of the pawl upon the ratchet-wheel attached to the spindleiof thetoollxolder. To retract the bit, throw out the boring-pawland engage the other one, whenthe samermotion of4 the crank withdraws the bit from the hole ithasbored.

Having thus fully described my invention, Y

l1. The combination; witlrthe" cifank ,of a brace, of the head A 'and armsv B and Opeenstructcd and operating as specified. n l y 2. The combination, withv the crank of 'a brace,'of' the jaws I K, sleeve Hg shaft G, spindle e, ratchetg wheels E F, and pawls f g," 1.fthe manner anflfor the purpose described.

The above specification. of'rny said` invention signed andwitnessed at Washington this 21st day of J une, A.l

WILLIAM lP. DOLIJ.

Witnesses:

E. G. HARBAUGB, CRAs. F. SrAn-SBURY.

desire-tosecure by Letters 

